There are already known various installations capable of sawing or otherwise subdividing and distributing or sorting plate-shaped objects, among them such including a subdividing arrangement that includes a plurality of sawing devices that perform longitudinal and transverse cuts and are thus capable of sawing a plate blank, which consists of a single plate or of a plate packet, into equal-width or different-width longitudinal and transverse strips in order to obtain in this manner from the plate blank a multitude of final products that may have different sizes. In such installations, it is also already known to transfer the respective final products to a plurality of stacking stations at which such products are stacked, and the thus obtained stacks are eventually transported by means of at least one roller conveyor that leads away from the installation to their destination or destinations.
One construction of the plate subdividing and resultant product conveying and stacking machine of this type is known, for instance, from the German published patent application DE-OS 27 02 725. In this machine, the final products which are obtained in a subdividing arrangement by subdividing or sawing plate-shaped blanks are sorted according to size to a plurality of roller conveyors that are arranged parallel next to each other. A stacking unit is associated with each of these roller conveyors and is operative for stacking the final products that are supplied thereto by the respective roller conveyor. Each of the final product stacks which is formed in the stacking unit of this type can be transported away from the stacking unit by means of a further roller conveyor, and is then supplied to a loading station.
Inasmuch as each of the roller conveyors which leads to the respective associated stacking unit is able to receive only final products having the same size, and of transporting such same-size final products to the associated stacking station, it is necessary to provide a large number of such roller conveyors with the associated stacking units, in order to enable the sawing or subdivision of the plate-shaped blank or preform by the sawing arrangement into a corresponding number of different final products.
Each of the final products may consist of a multitude of superimposed plate-shaped objects the number of which corresponds to the number of individual plates in the plate-shaped blank. The plate-shaped blank may be constituted by a single plate, or by a plate package.
It is also known in stacking installations which are arranged downstream of a sawing arrangement and which are operative for stacking the final products or objects that are obtained from the plate-shaped blank by sawing, to arrange two stacking units for the final products immediately next to one another. Then, a discharge roller conveyor is associated with the last one of these stacking units and serves for the transportation of the stacks of final products which are formed in both of these stacking units away from such units. To this end, the lifting tables of these two stacking units are arranged immediately next to one another in such manner that the stack that is formed on the lifting table of the front stacking unit can be transported, when the lifting table of the front stacking unit is in its lowermost position and the lifting table of the rear stacking unit is also in its lowermost position and is empty, via the lifting table of such rear stacking unit to the discharging or transporting-away roller conveyor that is situated at the elevation that corresponds to that of the lifting tables of the two stacking units when such lifting tables are in their lowermost positions.
However, this has the disadvantage that considerable time losses may be incurred in the transportation of the final product stack that has been formed on the front stacking unit away from such stacking unit, inasmuch as this type of transportation or discharge always makes it necessary to assure that the rear stacking unit is temporarily empty during such discharge, and that no stack is being formed thereon during this time. Consequently, the advantage of the arrangement of the two stacking units immediately next to one another for the transportation of the final products of different sizes to such adjacent stacking units, which results from the fact that such different-size final products are forwarded along the same path, is lost or largely lost in this manner.